Calculator
Enter all monetary amounts in the same currency. Results do not convert currency or replace lender, tax or investment documentation.
Method and inputs
Formula: monthly P&I = P x r(1+r)^n / ((1+r)^n - 1)
Inputs: Home price, down payment, fixed annual interest rate, loan term, annual property tax, annual insurance and optional monthly HOA fee.
Worked example
A $400,000 home with $80,000 down, a 6% fixed rate and a 30-year term has an estimated principal-and-interest payment of about $1,918.56 per month.
How the interest rate changes the payment
| Rate | Monthly principal and interest ($320,000, 30 years) | Total interest |
|---|---|---|
| 5% | $1,717.83 | $298,419 |
| 5.5% | $1,816.92 | $334,093 |
| 6% | $1,918.56 | $370,682 |
| 6.5% | $2,022.62 | $408,142 |
| 7% | $2,128.97 | $446,428 |
Each half-point of rate changes the payment by roughly $100 a month on this loan, and the total interest by tens of thousands of dollars over 30 years.
Important limits
This is an estimate for a fully amortizing fixed-rate loan. It excludes closing costs, lender fees, PMI, rate changes, escrow adjustments, points and local lending rules. Review your official Loan Estimate before deciding.